Dishwasher with cover latching mechanism



'Aug. 21, 1956 w, GUTH 2,759,485

DISHWASHER WITH COVER LATCHING MECHANISM Filed Nov. 50, 1.954

5 Sheets-Sheet l INVENTOR.

LAUREN W. GUTH HIS ATTORNEY Aug. 21, 1956 w. GUTH DISHWASHER WITH COVER LATCHING MECHANISM Filed Nov. 50, 1954 5 Sheets-Sheet 2 FIG.4

INVENTOR.

LAUREN w. GUTH HIS ATTORNEY Aug. 21 1956 w. GUTH 2,759,435

DISHWASHER WITH COVER LATCHING MECHANISM Filed Nov. 30, 1954 5 Sheets-Sheet 3 FIG.6

FIG. 7

IN V EN TOR.

LAUREN W. GUTH BY HIS ATTORNEY United States Patent DISHWASHER WITH COVER LATCHING MECHANISM Lauren W. Guth, Louisville, Ky., assignor to General Electric Company, a corporation of New York Application November 30, 1954, Serial No. 472,073

7 Claims. (Cl. 134-58) This invention relates to dishwashing apparatus and more particularly to cover locking and control mechanisms for such apparatus.

Dishwashing machines of the type to which this invention pertains are provided with means for rapidly circulating washing liquid throughout the tub in which the dishes are supported, and consequently it has been necessary to provide means for locking the cover in closed position during washing operations to prevent the spraying of hot water from the tub which would result if the cover were inadvertently opened. However it is sometimes necessary or desirable to open the cover of the machine to add or take out overlooked articles, and to permit this to be done some dishwashers heretofore developed have included a door operated interlock in the water circulating motor circuit. However, one disadvantage of such prior art dishwashers is that circulation of water throughout the tub cannot be stopped instantaneously by de-energization of the water circulating motor, and hence rapid opening of the tub cover may result in a spray of hot water into the room. This disadvantage applies both to automatic dishwashers and to dishwashers of the non-automatic type since the water circulating spray devices or impellers commonly used continue to operate for an appreciable period of time after the pump or motor driving them has been de-energized.

A principal object of the present invention is to provide an improved dishwasher having cover latching and control mechanism arranged to prevent opening of the washing compartment cover until water circulation within the compartment has ceased.

Another object of the invention is to provide an automatic dishwasher having improved cover control mechanism permitting interruption of a washing cycle for the addition or removal of articles in the washing tub.

Further objects and advantages of my invention will become apparent as the following description proceeds, and the features of novelty which characterize the inven tion will be pointed out with particularity in the claims annexed to and forming a part of this specification.

Briefly stated in accordance with one aspect of my invention, 1 provide a dishwasher having a cover latch which is held in locked position during washing operations by latch holding mechanism releasable by a manual control member arranged to independently prevent the latch from moving to unlocked position when it is actuated so as to release the latch mechanism. The arrangement is such that the cover may be unlocked only by initial movement of the control member so as to partially release the latch, and subsequent movement of the control member to another position so as to permit movement of the latch to unlocked position. Thus a time interval of at least a few seconds is assured between initial movement of the control member and opening of the cover, and by providing an interlock switch in the water circulator circuit opened by initial movement of the control member, this time interval is utilized to make sure that water circulation in the washing compartment has ceased before the cover is opened.

For a better understanding of my invention reference may be made to the accompanying drawing in which:

Fig. 1 is a front elevation of a dishwasher incorporating my invention, some of the parts being broken away to show details of construction.

Fig. 2 is a fragmentary side elevation partly in section of the same dishwasher.

Fig. 3 is a detail view showing a front elevation of the latch mechanism of the dishwasher, the parts being in locked position.

Fig. 4 is a sectional view taken substantially along the line 4-4 in Fig. 3.

Fig. 5 is similar to Fig. 3 but shows the parts in unlocked position.

Fig. 6 is similar to Fig. 3 but shows the parts in an intermediate partially released position.

Fig. 7 is a detailed sectional view taken substantially along the line 77 in Fig. 3.

Referring to the drawing, there is shown in Fig. 1 a dishwasher having a cabinet 1 enclosing a tub or vat 2 forming a washing compartment in which dishes and other articles may be supported on suitable racks or the like. The open top of tub 2 is closed and sealed by a cover 3 secured to the rear of the cabinet by means of a hinge 4 permitting the cover to be opened to a substantially vertical position. Cover 3 is spring biased to its open position by a spring 5 secured at one end to the rear wall of tub 2 and carrying at its other end a roller a engaging the under side of the cover. Suitable means are provided for admitting water or other washing liquid into tub 2 which may be in the form of a water inlet pipe 7 communicating with the interior of the tub by means of a funnel 8 spaced from pipe 7 so as to form an air gap. Inlet pipe 7 is of course connected by a hose or other suitable means to a water supply system and is provided with a timer controlled automatic valve (not shown) whereby water is admitted to the washing compartment only at appropriate times during the washing cycle. Tub 2 is equipped with a drain pump 9 also energized and controlled by a sequence timing device so as to drain water from the washing compartment at the end of each washing or rinsing cycle and at the completion of the washing operation. The pumping chamber of pump 9 is connected on its inlet side to tub 2 by means of a drain boot 10 while its outlet is connected to a drain line 11. Suitable means for circulating water throughout the washing compartment is of course required, and as shown in Fig. 1 a rotary impeller 12 driven by an electric motor 13 is provided for this purpose.

The water inlet valve in inlet line 7, drain pump 9 and impeller motor 13 are all connected in an electrical circuit energized by a suitable power supply line and are controlled by a sequence timing device 14 so that each is energized at appropriate times during each washing operation. Typically, a washing operation includes two rinsing cycles during which separate charges of water are admitted to the tub, circulated and then discharged by drain pump 9, a washing cycle at the beginning of which detergent is added to the water admitted to the tub, and two final rinse cycles followed by a drying period during which the cover is opened to promote air circulation. In the present embodiment timer 14 is mounted at the front of the cabinet 1 in the lower right-hand corner and is provided with a sprocket 15 rotated by the timer motor. For the purpose of setting the timer and also indicating the position of the timer mechanism a control member 16 mounted for both rotary and reciprocating movement on a shaft 17 is provided, it being most' conveniently located on the front wall of the cabinet 1 ad U jacent the upper edge thereof. Shaft 17 on which the control member is mounted also carries a sprocket 18 which is connected in driving relation with sprocket by means of a chain 19.

In accordance with the present invention 1 provide cover latch and control mechanism for the cover 2 of the dishwasher described above. Referring to Fig. 3, there is illustrated a latch assembly comprising a mounting plate 20 upon which the various parts and elements are supported and which is secured to the outer surface of the front wall of tub 2. Cooperating with the latch assembly is a catch 21 in the form of a U-shaped metal strip rigidly secured to the front edge of cover 3. Catch 21 is adapted to be engaged by a pivoted latch member 22 carried by a shaft 23 extending through plate 23. To guide catch 21 into engagement with latch 22, and prevent lateral movement of the catch in the locked position, a catch guide 2311 is secured to plate 2t) and tub 2. Latch member 22 includes a cam portion 24 initially engaged by catch 21 as cover 3 is closed, and a hook portion 25 adapted to engage the catch as the latch member 22 is pivoted into its locked position upon further movement of cover 3 toward its closed position.

Also mounted on shaft 23 for pivotal movement with latch member 22 is a latch arm 26, the free end of which engages a slide member 27 mounted for reciprocating movement on mounting plate 23. Slide member 27 is secured to plate 20 by means of a pair of studs 28 and 29 projecting from the plate and extending through slots 30 and 31 respectively in the slide member. The side edges of slide member 27 are turned up to form a pair of spaced flanges 32 and 33 parallel to the line of movement of the slide. Latch arm 26 projects through an opening in flange 32 and preferably engages an adjusting plate 34 adjustably secured to flange 32. Slide member 27 is biased by means of a spring 35 against a stop plate 36 as shown in Fig. 5, it being noted that one end of spring 35 is secured to a tab 37 at one end of the slide while the other end is secured to stud 29. From the description thus far it will be observed that latch member 22 is biased to its unlocked position( shown in Fig. 5) by spring 35 and that slide 27 and latch 22 are interconnected by latch arm 26; thus latch 22 pivots between locked and unlocked positions in accordance with reciprocating movement of slide 27.

Latch member 22 and slide member 27 are maintained in the locked position shown in Fig. 3 by a trip lever 38 having an arm 39 engageable with flange 33 of slide 27. Arm 39 of the trip lever extends generally parallel to and between flanges 32 and 33 when slide 27 is in the unlocked position shown in Fig. 5, and its end portion is arranged to pivot into engagement with the edge of flange 33 when slide 27 is shifted upwardly and to the right (as viewed in Fig. 5) by closing movement of cover 3. Trip lever 38 also operates means for energizing and de-energizing the dishwasher, and includes an arm 40 in engagement with the free end of a cantilever spring 41 secured to a switch 42 so as to maintain the contacts of the switch in closed position when trip lever 38 is in the position shown in Fig. 3 and to open the switch contacts when the trip lever is pivoted to the unlocked position shown in Fig. 5 or the intermediate position shown in Fig. 6. Switch 42 is connected in the circuit supplying energy to impeller motor 13 and timer 15 so that this circuit is interrupted when the switch contacts are open. Cantilever spring 41 applies a clockwise biasing force (as viewed in Fig. 3) to trip lever 38 and hence arm 39 of the trip lever is biased from the position shown in Fig. 5 to the position shown in Fig. 3 when slide 27 is shifted by rotation of latch member 22 upon closure of cover 3.

Trip lever 38 is pivoted from the position shown in Fig. 3 (locked position) to the intermediate position of the mechanism shown in Fig. 6 by means of force applied to a cam follower 43 formed on a third arm 44 of the trip lever. Preferably arm 44 is adjustably secured to the body of the trip lever by a screw and slot connection as shown, but insofar as its function is concerned it will be understood that arm 44 may be an integral part of the trip lever.

The latch mechanism mounted on plate 20 is manually controlled by rotary control member 16 which includes a knob portion 45, sprocket 18, cam 46 including projecting portions 47 and 48, and a cam 49 including projections 50 and 51 thereon. The arrangement is such that rotation of the control member 180 degrees corresponds to a complete cycle of operation. As best shown in Fig. 7 these elements are all mounted co-axially on shaft 17 projecting from mounting plate 20, and are secured together by a pair of screws 52 and 53 to form a unitary control member. Rotary control member 16 is mounted for reciprocating movement between an outer position in which a detent spring 54 carried thereby snaps into one of two spaced circumferential grooves in shaft 17 and another position in which the spring snaps into the other of the circumferential grooves. In the outer position which control member 16 normally occupies (see Fig. 7) cam 46, which cooperates with cam follower 43 actuates trip lever 38 by causing it to pivot in a counterclockwise direction only when one of the two projections 47 or 48 on the cam contacts the cam follower upon rotation of the control member. Hence so long as control knob 16 is in its outer position, slide 27 can be released from the position shown in Fig. 3 and the cover thereby opened only after knob 16 has been rotated (either manually or by timer 14) to a position corresponding to the end of the washing cycle.

However it will be observed from Fig. 7 that the inclined end portion of earn follower 43 projects under the edge of cam 46, and that inward movement of control member 16 toward plate 20 to its inner position will exert a force on cam follower 43 which will cause trip lever 38 to pivot counterclockwise thus releasing slide 27 (if the parts are in the position shown in Fig. 3) so that it can move to the position shown in Fig. 6. It will be observed however that movement of control member 16 to its inner position causes cam 49 to be shifted into the path of movement of slide 27, and that if the slide is released in this manner earn 49 obstructs its path of movement and restrains it from moving into engagement with stop 36. Thus the slide is held in an intermediate position in which latch member 22 is maintained in locking engagement with catch 21 on cover 3. Hence inward movement of control member 16 shifts trip lever 33 sufiiciently to open switch 42 and release slide 27 into engagement with cam 49, but does not unlock cover 3. To unlock the cover it is necessary to subsequently move control member 16 back to the position shown in Fig. 7, thus withdrawing cam 49 from the path of movement of slide 27 and permitting it to continue its movement into engagement with stop 36 so as to pivot latch member 22 out of locking engage ment with catch 22 on the cover.

Also mounted for pivotal movement on mounting plate 20 and positioned inside of tub 2 is a detergent holding cup 55 arranged to be actuated to its dumping position, in which detergent held therein is discharged into the tub, when control member 16 is rotated to a predetermined angular position. Detergent cup 55 is spring biased to inverted position as shown in Fig. 5 by a spring 56 connected at one end of an ear projecting from a latch ing arm 57 pivoted on mounting plate 20 and at its other end to a crank arm 58 projecting from a latch wheel 59 secured to the shaft on which cup 55 is mounted. Trigger arm 57 also includes a cam follower 60 cooperating with cam 49, the width of the cylindrical cam surface of cam 49 being substantially greater than the thickness of cam follower 60, so that the follower rides on this cam surface without interfering with the axial movement of control member 16 previously described. As shown in Fig. 7, the surface of cam 49 extends within a recessin cam 46, and follower 60 is inclined with respect to arm 57 u so as to travel into this recess upon inward axial movement of control member 16. Arm 57 is shifted out of engagement with a notch in wheel 59 so as to release cup 55 from its upright position when the cam follower is contacted by either of projecting portions 50 and 51 on cam 49. Cup 55 is then rotated by spring 56 to inverted position, and by this means a suitable quantity of powdered or liquid detergent may be automatically added to the tub at the beginning of the washing cycle. To prepare cup 55 for a subsequent washing cycle, it is manually rotated against the bias of spring 56 to its upright position (shown in Fig. 3) so that the necessary quantity of detergent may be deposited therein.

In describing the operation of my invention it will be assumed that dishes have been loaded into suitable racks supported in tub 2, that the water inlet and drain lines have been suitably connected to a water supply system and drainage system respectively, and that detergent has been placed in the detergent cup. Referring to Fig. 5, When the cover is open the parts are in the positions shown therein it being noted that cam portion 24 of latch member 22 is in position to be contacted by catch 21 on cover 3 as it is closed. When the cover is closed latch 21 strikes the cam portion 24 of the latch member, forcing the latch to rotate counter-clockwise until hook portion 25 engages the catch on the cover. As latch 22 rotates latch arm 26 also rotates forcing slide member 27 to move upwardly and to the right against the force of spring far enough to permit trip lever arm 39 to drop down and catch on the end of flange 33 of slide 27. When the trip lever has engaged slide 27 switch arm 41 is released and the contacts of switch 42 are closed.

The dishwashing cycle is started by turning control knob 16 clockwise to its on position in which interlock switch 42 is closed and a pair of contacts in the timer 14 are closed so as to energize impeller motor 13 and the timer motor. The washing operation under the control of the timer is thus initiated and the dishes are automatically pro-rinsed, washed and finally rinsed in the usual manner. Shortly after the final rinse has been completed one of the projections on cam 46 contacts cam follower 43, causing trip lever 38 to rotate counterclockwise, thus opening the interlock switch and releasing slide member 27 for movement into contact with stop 36. This movement of slide 27 causes pivotal movement of latch member 22 into its unlocked position as previously explained, and thus cover 3 is free to be opened by spring 5.

If it is desired to shut off the dishwasher during the cycle, for the purpose of adding or removing dishes for example, or to repeat part of the cycle, control knob 16 is first pushed to its inner position so as to cause the parts of the latch mechanism to shift to the position shown in Fig. 6. As knob 16 is shifted to its inner position the edge of cam 46 strikes the inclined surface on cam follower 43, forcing the cam follower away from the cam and thus causing trip lever 38 to rotate in a counterclockwise direction so as to open switch 42 and release slide 27 for movement under the influence of spring 35. However before slide 2'7 has moved far enough to rotate hook portion 25 of the latch member out of engagement with catch 21 the end of the slide strikes cam 49 which is of course simultaneously shifted into its path of movement by inward movement of knob 16. Consequently the water circulating impeller in the tub is de-energized and ceases to spray liquid throughout the washing compartment before the cover can open inasmuch as control knob 16 must be pulled out to its initial position to unlatch hook 25 from engagement with catch 21.

After the cover has been opened in this manner the parts are in their initial positions as illustrated in Fig. 5, and it is only necessary to close the cover so as to shift slide 27 to the position shown in Fig. 3 if it is desired to continue the dishwashing cycle from the point at which it was interrupted, it being understood that in this case control knob 16 is allawed to remain in the same angular position during the cover opening operation. To repeat or skip a cycle it is only necessary to rotate control knob 16 to the desired position.

While I have illustrated and described a specific embodiment of my invention, I do not desire my invention to be limited to the particular construction shown and described and I intend by the appended claims to cover all modifications within the true spirit and scope of my invention.

I claim:

1. A control and cover latching mechanism for dishwashing apparatus including a washing compartment, electrically energized means for circulating water therein, a cover for said compartment, and a catch on said cover, said mechanism comprising an interlock switch for interrupting the circuit supplying energy to said water circulating means, a latch member mounted for pivotal movement from an unlocked position to a locked position in engagement with said catch, a latch arm mounted for pivotal movement with said latch member, a slide member engaging said latch arm and mounted for reciprocating movement between a first position and a second position in accordance with pivotal movement of said latch member between its unlocked and locked positions respectively, means for biasing said slide member to said first position, tripping means for releasably holding said slide member in said second position and said switch in its closed position, and manually operable control means for actuating said tripping means so as to release said slide member for movement to its first position and open said switch, said control means including means for obstructing movement of said slide member to itsfirst position, said control means being movable between a first position out of engagement with said tripping means and said slide member and a second position in actuating engagement with said tripping means in which it obstructs movement of said slide member, whereby said cover can be unlocked only after initial movement of said control means from its first position to its second position so as to de-energize said water circulating means and subsequent return movement of said control means to its first position so as to release said slide member for movement to its first position.

2. A control and cover latching mechanism for dishwashing apparatus including a washing compartment, electrically energized means for circulating water therein, a cover for said compartment, and a catch on said cover, said mechanism comprising an interlock switch for interrupting the circuit supplying energy to said water circulating means, a latch member mounted for pivotal movement from an unlocked position to a locked position in engagement with said catch, said latch member having a cam portion initially engaged by said catch as said cover is closed and a hook portion adapted to engage said catch as said latch member is pivoted into its locked position upon further movement of said cover toward its closed position, a latch arm mounted for pivotal movement with said latch member, a slide member engaging said latch arm and mounted for reciprocating movement between a first position and a second position in accordance with pivotal movement of said latch member between its unlocked and locked positions respectively, a spring biasing said slide member to said first position, a trip lever mounted for pivotal movement adjacent said slide member and having a first arm engageable therewith so as to hold said slide member in said second position, a second arm in engagement with said switch, and a third arm provided with a cam follower, means for biasing said trip lever so that said first arm is pivoted into holding engagement with said slide member and said switch is closed when said slide member is moved from its first position to its second position by pivotal movement of said latch member upon closure of said cover, and a manually operable control member including a cam mounted for reciprocating movement between a first position in which it is out of engagement with the cam follower on said third arm of said trip lever and a second position in which it engages said cam follower so as to pivot said trip lever out of holding engagement with said slide member, said control member including an element which obstructs movement of said slide member to its first position when the control member is moved to its second position, whereby said cover can be unlocked only after initial movement of said control member from its first position to its second position so as to deenergize said water circulating means and subsequent return movement of said control member to its first position so as to release said slide member for movement to its first position.

3. A control and cover latching mechanism for dishwashing apparatus including a Washing compartment, electrically energized means for circulating water therein, a cover for said compartment, and a catch on said cover, said mechanism comprising an interlock switch for interrupting the circuit supplying energy to said water circulating means, a latch member mounted for pivotal movement from an unlocked position to a locked position in engagement with. said catch, said latch member having a cam portion initially engaged by said catch as said cover is closed and a hook portion adapted to engage said catch as said latch member is pivoted into its locked position upon further movement of said cover toward its closed position, a latch arm mounted on a common shaft with said latch member for pivotal movement therewith, a slide member engaging said latch arm and mounted for reciprocating movement along its axis in a plane perpendicular to the axis of said common shaft between a first position and a second position in accordance with pivotal movement of said latch member between its unlocked and locked positions respectively, said slide member having a pair of spaced flanges parallel to its line of movement, a spring biasing said slide member to said first position, a trip lever mounted for pivotal movement adjacent said slide member and having a first arm engageable therewith so as to hold said slide member in said second position, a. second arm in engagement with said switch, and a third arm provided with a cam follower, said first arm extending generally parallel to and between said flanges when said slide is in its first position, means for biasing said trip lever so that the end portion of said first arm is pivoted into holding engagement with said slide member and said switch is closed when said slide member is moved from its first position to its second position by pivotal movement of said latch member upon closure of said cover, a manually operable control member including a cam mounted for reciprocating movement between a first position in which it is out of engagement with the cam follower on said third arm of said trip lever and a second position in which it engages said cam follower so as to pivot said trip lever out of holding engagement with said slide member, said control member including an element which obstructs movement of said slide member to its first position when the control member is moved to its second position, whereby said cover can be unlocked only after initial movement of said control member from its first position to its second position so as to de-energize said water circulating means and subsequent return movement of said control member to its first position so as to release said slide member for movement to its position.

4. A control and cover latching mechanism for dishwashing apparatus including a time switch having a rotary shaft for sequentially controlling electrically energized means for circulating water therein, said mechanism comprising an interlock switch for interrupting the circuit supplying energy to said water circulating means, a washing compartment cover, and latch mechanism for said cover including a catch on said cover, a pivoted latch member on said tub, a latch arm mounted for pivotal movement of said latch member, a slide member engaging said latch arm and mounted for reciprocating movement between a first position and a second position in accordance with pivotal movement of said latch member between its unlocked and locked positions respectively, a spring biasing said slide member to said first position,

tripping means for releasably holding said slide member in said second position and said interlock switch in its closed position, a manually operable rotary control member having a driving connection with said time switch shaft and including a cam cooperating with said tripping means and arranged to actuate said tripping means so as to release said slide member and open said switch when said control member is rotated to a predetermined angular position, said control member being mounted for reciprocating movement between a first position in which said cam actuates said tripping means only when said control ember is in said predetermined angular position and a second position in which said tripping means is actuated by said cam regardless of its angular position, said control member including an element which obstructs movement of said slide member to its first position when the control member is moved to its second position, whereby said cover can be unlocked only after initial movement of said control member from its first position to its second position so as to d e-energize said water circulating means and subsequent return movement of said control member to its first position so as to release said slide member for movement to its first position.

5. A control and cover latching mechanism for dishwashing apparatus including a washing compartment, electrically energized means for circulating water therein, a cover for said compartment, and a catch on said cover, said mechanism comprising an interlock switch for interrupting the circuit supplying energy to said Water circulating means, a latch member mounted for pivotal movement from an unlocked position to a locked position in engagement with said catch, a slide member interconnected with said latch member and mounted for reciprocating movement between a first position and a second position in accordance with the pivotal movement of said latch member between its unlocked and locked positions respectively, means for biasing said slide member to said first position, a trip lever mounted for pivotal movement adjacent said slide member and having a first arm releasably engageable therewith so as to hold said slide member in said second position and a second arm in engagement with said switch, means for biasing said trip lever so that said first arm is pivoted into holding engagement with said slide member and said switch is closed when said slide member is moved from its first position to its second position by pivotal movement of said latch member upon closure of said cover, and manually operable control means for releasing said trip lever and independently restraining said slide member from moving to its first position, whereby said cover can be unlocked only after initial movement of said control means so as to open said switch and subsequent movement thereof so as to release said slide member.

6. A control and cover latching mechanism for dishwashing apparatus including a time switch having a rotary shaft for sequentially controlling electrically energized means for circulating water therein, said mechanism comprising an interlock switch for interrupting the circuit sup plying energy to said water circulating means. a wash ing compartment cover and latch mechanism for said cover including a catch on said cover, a pivotal latch member on said tub, a latch arm mounted for pivotal movement with said latch member, a slide member engaging said latch arm and mounted for reciprocating movement between a first position and a second position in accordance with pivotal movement of said latch member between its unlocked and locked positions respectively, said slide member having a pair of spaced flanges parallel to its line of movement, a spring biasing said slide member to said first position, a trip lever mounted for pivotal movement adjacent said slide member and having a first arm engageable therewith so as to hold said slide member in said second position, a second arm in engagement with said interlock switch, and a third arm provided with a cam follower, said first arm extending generally parallel to and between Said flanges when said slide is in its first position,

means for biasing said trip lever so that the end portion of said first arm is pivoted into holding engagement with said slide member and said switch is closed when said slide member is moved from its first position to its second position by pivotal movement of said latch member upon closure of said cover, and a manually operable rotary control member having a driving connection with said time switch shaft, said control member including a cam cooperating with said cam follower and arranged to shift said trip lever so as to release said slide member and open said switch when the control member is rotated to a predetermined angular position, said control member being mounted for reciprocating movement between a first position in which said cam engages said cam follower only when the control member is in said predetermined angular position and a second position in which said cam follower is engaged by said cam regardless of its angular position, said con trol member including an element which obstructs movement of said slide member to its first position when the control member is moved to its second position, whereby said cover can be unlocked only after initial movement of said control member from its first position to its second position so as to de-energize said water circulating means and subsequent return movement of said control member to its first position so as to release said slide member for movement to its first position.

7. A control and latching mechanism mounted for locking engagement with a cooperating catch member and for controlling the operation of other apparatus comprising latch means movable from an unlocked position into locking engagement with said catch member, reciprocating means mounted for movement between a first position and a second position in accordance with the movement of said latch means between its unlocked and locked positions respectively, means for biasing said reciprocating means to said first position, energizing means for said other apparatus normally occupying a first position in which said other apparatus is inoperative but movable to a second position in which said other apparatus is operative, tripping means for releasably holding said reciprocating means in its second position and said energizing means in its second position, and manually operable control means movable from a first position out of engagement with said tripping means to a second position in which said tripping means is engaged and released and said reciprocating means is restrained by said control means from movement to its first position, whereby said cover can be unlocked only after initial movement of said control means from its first position to its second position so as to move said energizing means to its first position and subsequent movement of said control means to its first position so as to release said reciprocating means.

Wolf Nov. 17, 1953 Stanitz Oct. 26, 1954 

